Leo Szilard

Leo Szilard (11 February 1898-30 May 1964) was a Hungarian-American physicist and inventor. He patented the nuclear reactor with Enrico Fermi in 1934 and wrote the letter for Albert Einstein's signature that resulted in the start of the Manhattan Project in 1939.

Biography
Leo Szilard was born in Budapest, Austria-Hungary in 1898, and he attended the Palatine Joseph Technical University in Budapest before serving in the Austro-Hungarian Army during World War I. He emigrated to the German Empire in 1919 and studied physics at Friedrich Wilhelm University, recognizing the connection between thermodynamics and information theory. He patented the linear accelerator in 1928 and a cyclotron in 1929, and he also conceived the idea of an electron microscope. From 1926 to 1930, he worked with Albert Einstein on the development of the Einstein refrigerator. In 1933, he emigrated to England following the rise of Nazi Germany, and he discovered a means of isotope separation and provided jobs to fellow Jewish refugees. In 1938, he moved to the United States and worked with Enrico Fermi and Walter Zinn on creating a nuclear chain reaction. He was present when it was achieved on 2 December 1942, and he helped to design nuclear reactors for the Manhattan Project. After the end of World War II in 1945, Szilard switched to biology, inventing the chemostat, discovered feedback inhibition, and was involved in the first cloning of a human cell. He helped found the Salk Institute for Biological Studies before dying in 1964.